LG Plasma TV Model No. 50PJ550

[baggjn]

Re: LG Plasma TV Model No. 50PJ550

From what I have been reading on this forum threads I believe what is known as the Z-sus board is also known as the Main Logic Board in a LG Plasma, have I got that right? can anyone please advise if I am right or wrong?

[Alastair E]

Re: LG Plasma TV Model No. 50PJ550

Nah--Logic board is the small sub-board in centre of set--I seriously doubt its that.

Still looks like VSc/-Vy type issue on Y-sus to me...

[sugar_ray]

Re: LG Plasma TV Model No. 50PJ550

Nope!! Z sus and logic are 2 completely things. This set is a nightmare to diagnose. If it's the one I'm thinking, the power supply feeds the Y board and the Y board then supplies power through a seperate harness to the Z board. From my experience, when one of these boards goes it takes out another!! I really don't like how LG intertwined these units like that!! Your logic board on this model is in the centre at the bottom part of the back panel. It will have a small LED light blinking indicating it's working ok.

I had did a complete board swap (z,y,ps, and both y buffers) on this set with so called known working boards.All I got was the same black cloudy spots you did. The tv ran this way for about 5 minutes then pop!! The fuse on the Zboard went bad. Replaced it and tv would only relay click when turned on.

That was enough fun for me. Especially for an outdated 720p LG. The problem you may discover is finding a reasonably priced Y board replacement. Ebay, and anywhere else was asking waaaaay more then it's worth to fix. Not sure why?? These boards aren't gold

[baggjn]

Re: LG Plasma TV Model No. 50PJ550

Thanks again Alister and sugar ray, I get it now. sugar ray surely, if it was fixed, the sell on price, to help buy a 1080p would be worth cost don't you think?

[Alastair E]

Re: LG Plasma TV Model No. 50PJ550

Thanks again Alister and sugar ray, I get it now. sugar ray surely, if it was fixed, the sell on price, to help buy a 1080p would be worth cost don't you think?

Well,--yes, what I did,-- a little profit in the pot each time, and eventually I ended up with a S/H 4 month old 4K set!

defo worth it--but obviously the profit on that set if you need to replace an expensive board is much lower--The skill is determining when its just Not going to give you any profit at all, At that point best flog it on ebalag.....

[tw2005]

Re: LG Plasma TV Model No. 50PJ550

Old threads die hard but you can always add.

I picked up the same model, same black holes in the image. must admit struggled with it .

YSUS, check all high wattage low ohm resistorss for open cct, e.g. 2.2ohm there's about 5 of them. I had 1 open and fixed this problem however I have some sparkles still so not a complete success.

Should help someone in the future hopefully. There is another thread which mentions these resistors, still searching for it.